Category Archives: Features

If you’re in love with space exploration then you’ll fall for this: it’s the picture of Earth taken from the Voyager 1 spacecraft after it passed the orbit of Pluto in 1990. That image of our planet from almost 4 billion miles away inspired Carl Sagan to write his famous “Pale Blue Dot” passage, and reminds us that we are all just floating on “a mote of dust suspended in a sunbeam.”

This is from a post I originally published in 2010. I’ll keep trotting it out until it’s not cool anymore. (Which I don’t think will ever happen.)

Venus, Earth, Jupiter, Saturn, Uranus and Neptune as seen by Voyager 1 in 1990 (Credit: NASA)

On February 14, 1990, after nearly 13 years of traveling the solar system, the Voyager 1 spacecraft passed the orbit of Pluto and turned its camera around to take a series of photos of the planets. The image above shows those photos, isolated from the original series and are left to right, top to bottom: Venus, Earth, Jupiter, Saturn, Uranus, and Neptune.

From that distance, over 4 billion miles from the Sun, the planets each appear as little more than a bright dot against the vastness of interplanetary space.

“That’s here. That’s home. That’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. … There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world.”

Note: this post was first published on Feb. 22, 2011. I’m reposting it again today because 1. the video creator has since updated the soundtrack, and 2. it’s still awesome.

One of the things that fascinates me so much about the Universe is the incredible vastness of scale, distance and size.

On Earth we have virtually nothing to compare to the kinds of sizes seen in space. We look up at the stars and planets in the night sky but they are just bright points of light. Some brighter, some larger, some slightly different colors. But they’re still just points from where we stand. Even from space, seen by telescopes or by astronauts in orbit….still just points.

It’s “Pi Day” (March 14… 3.14… get it?) and, based on how we write the date in the U.S. anyway, all those of a sufficiently geeky nature take a moment to honor the universal usefulness of pi, the glorious Greek letter used to represent the mathematical ratio of a circle’s circumference to its diameter.

The basics of pi were known to the Babylonians over 4,000 years ago, and a method to determine pi to any degree of accuracy needed was developed by Archimedes in the third century BCE. Now, the value of pi has been calculated to many trillions of decimal places and its practical uses have extended far beyond the surface of our planet, helping engineers plot the orbits of planetary spacecraft and even measure the sizes of planets outside our solar system!

In fact NASA uses pi all the time in various extraterrestrial applications… read more:

This is from a post I originally published in 2010. I’ll keep trotting it out until it’s not cool anymore. (Which I don’t think will ever happen.)

Venus, Earth, Jupiter, Saturn, Uranus and Neptune as seen by Voyager 1 in 1990 (Credit: NASA)

On February 14, 1990, after nearly 13 years of traveling the solar system, the Voyager 1 spacecraft passed the orbit of Pluto and turned its camera around to take a series of photos of the planets. The image above shows those photos, isolated from the original series and are left to right, top to bottom: Venus, Earth, Jupiter, Saturn, Uranus, and Neptune.

From that distance, over 4 billion miles from the Sun, the planets each appear as little more than a bright dot against the vastness of interplanetary space. And Voyager was still a long ways off from reaching the “edge” of our solar system, the bubble of energy emitted by the Sun in which all of the planets, moons, and asteroids reside. In fact, Voyager 1 still has an expected five years to go before it crosses that boundary and truly enters interstellar space.*

“That’s here. That’s home. That’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. … There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world.”

Have you ever seen a meteor streak across the night sky? How about a very bright fireball (aka bolide), one that seemed to disintegrate in front of your eyes or leave a trail of vapor that hung in the air for a few moments? These “shooting stars” are actually tiny bits of rock and dust that exist everywhere in the Solar System, and when they run into Earth’s atmosphere they are slowed down incredibly, resulting in a transfer of energy that releases light and heat — usually enough heat to vaporize the original object entirely. But on occasion a large and/or dense enough object enters the atmosphere and survives the blazing journey to the surface. If it hits land, the meteorite (or its remaining pieces) might one day be discovered by a random traveler, a hiker, a farmer… or a even dedicated “meteorite man” like Geoff Notkin.

Author, educator, and host of Science Channel’s “Meteorite Men” and Cox7’s STEM Journals, Geoff Notkin has dedicated his life to the study, collection, and dealing of these “inert aliens” from outer space. His Tucson-based company, Aerolite Meteorites, sells some of the specimens that he’s traveled around the world to find, and last week I had the chance to talk with Geoff about his business and his passion and learn more about what got him so interested in meteorites to begin with.

I’m sorry, let me elaborate: physics is really hard. The sharpest minds of our entire species have been hammering away at the fundamental rules of our Universe for the past several hundred years, and while they’ve discovered an incredible lot about the tiniest bits of things that make up… well, everything… it’s still hard. There are still a lot of questions, and a lot to learn and find out, and all of it is just terribly scientific and mathematical and counter-intuitive to anything you might think you know about how stuff works.

Thankfully, author and physicist Dave Goldberg is here to explain it all… or at least give you a working familiarity with the basics. And yes, there are basics. (Even in physics.)

Voices of Exploration

"I think there’s something to seeing these very professional people helping each other to solve a problem and in the idea that mankind is humane and will do the right thing eventually to each other and to others...we all like the idea that there are great mysteries still to be explored.”
— Leonard Nimoy (1931–2015)

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